Really need to back the bus up and figure why the barrel project was abandoned in the first place.

Is the head space too long, chamber chatter marked, or egged out from floating reamer holder not being used in the first place.
Or is the problem that rifling either too screwed up, burned out, or bore wrong since to begin with as well.  Hence any of these problems will yeild the barrel useless, since there is no way to add metal back on  to correct such problems.


As for port drilled with 3/32" bit, it's now .9375", plus check run out.

So should be,
16" barrel, .625" dia., 8.375" from muzzle;
Port sizes from .063" to 078"
16" barrel, .750" dia., 8.375" from muzzle;
Port sizes from .070" to .086"

So if the rest of the barrel is fine and useable, and just comes down to the gas port the problem, easy enough to tig weld the top of channel closed, and just drill the port the correct needed size instead.